Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by Weld Racing

Welcome to ThirdGen.org!

Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!

I am trying to get my new 383 started and I am having no luck at all. The engine just rotates and rotates. it will not start. After about 7 seconds of the engine rotating, its starts to rotate slow like something is binding up. I am 99% sure nothing is binding up though. Then once I give up I turn the key to the off position and wait a little while. WHen I go to the turn key to the run position, I hear this loud rush of air coming from the engine somewhere. I think its coming from the TB. What is causing this air to rush out if all I am doing is turning the key to the run position. All that should be happening is the fuel pump pressurizing the system. I have 2 fuel pressure gauges and they both show 40PSI when I turn the key foward. Also every once in a while the car will back fire and almost start but it never does. If is is back firing, then I must have spark at least and I just had my MSD dizzy rebuilt a few weeks ago. I also pulled the plugs and they where wet with gas which means that fuel IS getting to the engine. Everything on this engine is brand new. what the heck is causing this? I also have been messing around with the timing but I cant get it to even start anywhere in the timing range. Even if the timing was off a little, the engine should still start up at least. mods are in sig.

Find #1 firing (which one out of the 2 instances of #1 TDC during one complete engine cycle) by sticking a piece of rubber tubing or something in the #1 spark plug hole, bumping the motor over slowly in small steps until you hear compression coming out ot that place, and continuing to bump it in the smallest possible steps until the timing mark is at about 10-15° BTDC. Then take a look at where your rotor is pointing. I'm guessing it won't be pointing to where the #1 plug wire is.

Either pull the dist out enough to allow you to rotate the shaft around to where the rotor points the right way; or move the plug wires around to match the rotor. I prefer the first method. The #1 plug wire should be on the very front of the dist, just to the driver's side of straight ahead; then clockwise around the cap, 18436572.

I have already done that. I had a budy put his finger on the #1 plug hole and I turned theengine until it started blowing air out. continued to do this until the timing marks started appearing near the pointer. I then continued until the timing pointer was on 0 degrees. I did this while the dist was in the car. I then instaled the cap and made sure that the rotor was pointing at the #1 terminal on the cap where I would put the #1 plug wire. I then did the normal rotation of the wires like they are suppose to go. I will try this again with the dist out and go from there but I am prety sure I did the procedure the correct way. I dont think it matters where the rotor points to in relation to the engine as long as it points to where the #1 plug wire goes on the cap. and just for the record it just so happens that mine was pointed troward the #1 plug on the head.

might not be 180 out, but I agree with RB, it sounds like the timing is off. Have your buddy grab the distributor and move it back and forth while you try to start the car until it fires up... just dont fuel foul the plugs or you'll never get it started lol.

UPDATE:
I took the dizzy out today, found TDC and reinstalled the dizzy again. I hooked everything back up like normal and the engine just spits out air while its cranking. It hisses out air through the TB. I went and spun the dizzy CCW a little bit and tried it again and got the same results. I spun it more and got the same results. I have a signal at the tach and while cranking the tach needle is moving. ( I mention this becuz I think someone said check for a signal there) I also did all this while the ESC wire was disconnected. I am stumped here. I have done a few dizzy installs w/o any issues at all. I turn the engine until I can feel and hear air pushing out the plug hole. I then check the timing marks on the balancer and they get closer to the timing mark as air pushes out the hole. So that must mean that I am on the compression stroke right? Once I get to that point at TDC I then stick a long screwdriver in the engine and turn the oil pump rod so the groove is pointing toward the #1 cylinder. I then drop the dizzy in and ensure the rotor points to the # 1 terminal on the cap. THis is correct right. If for some reason the rotor didnt line up perfectly then I just turn the shaft a little bit so it lines up once I drop the cap back on. What is going on here. Could I have some sort of mechanical failure here? I had this engine running once and I had to have the machine shop take it back apart due to an unbalanced crank. They fixed it and reassembled what they took out. Could there be something installed wrong(which I highly doubt but anythings possible)

its not the rockers, I had this engine running already for a few miles untilI had othave the crank pulled out tobe rebalanced. I know the engine runs just fine with the rockers being tightened the way they are. Nothing has changed in the top end of this engine since it was last running. just the renmoval and insatallation of the crank, 1 piston and 1 rod.

are you sure that you put the crank back in right? With the lines lining up on the timing sprockets? With air coming out the TB, it seems like on your exhaust stroke the cam has the intake open, and vice-versa by your description...

Originally posted by sellmanb are you sure that you put the crank back in right? With the lines lining up on the timing sprockets? With air coming out the TB, it seems like on your exhaust stroke the cam has the intake open, and vice-versa by your description...

you beat me too it even though you posted well before me
but yeah when reading this I was thinking same thing came and crank are not looking like they are timed together

you want to make sure about it try rotating the crank by hand or tapping the starter with the valvecovers off using your good ol' friend again putting his finger near the spark plug hole..
what your prolly going to see is when the air blows by his finger next thing to open up is going to be the intake valve rather then the exhuast valve

rx7speed, what is the correct way that the valves should be moving at while I turn the engine by hand? what should I be looking for if all should be correct? The machine shop put this engine together and I got it running w/o any issues but then the crank had to come back out cuz the engine had a vibration to it that I didnt like so I had it all rebalanced. The machine shop took out the crank, one rod and one piston I think. They had to remove at least one head to do that and I had told them to remove the other head and inspect the pistons and everything just to make sure that while i had it running that everything else was fine. So both heads where off and then everything was put back togheter. The cam stayed in the engine as well as 7 pistons and rods. If the remaining 7 pistons and rods where left untouched in the engine then the crank should only be able to go back in in the same way it was right? That way the rods would be able to bolt up to the crank in the same postion they stopped in right?

When you put the crank back in, how did you line up the dots on the cam gear and crank gear? 6 on the cam and 12 on the crank (dots nearest each other) ? If so, you're on number 6 firing, not 1. If you install dot-to-dot, you must rotate the crank one complete revolution in order to drop the distributor in on number one.

To elaborate on the above mentioned, pull the cap off the dizzy, and the driver's side valve cover off. Remove number one spark plug. place finger in hole while someone cranks the engine in very small turns (just a touch on the key). When you feel the air rush out, check to see where the timing mark is on the balancer and the rotor position. If it is past zero already, do not turn it ahead. Turn it back by hand to 4 or 6 degrees before TDC(it won't hurt it) and check again.

You can also turn it by hand (easier if you pull all the plugs) and watch for the number one intake valve to open and close again, and take notice to where the rotor on the distibutor is pointing.

Originally posted by Zed'er If it is past zero already, do not turn it ahead. Turn it back by hand to 4 or 6 degrees before TDC(it won't hurt it) and check again.

You can also turn it by hand (easier if you pull all the plugs) and watch for the number one intake valve to open and close again, and take notice to where the rotor on the distibutor is pointing.

I do not totally understand what you mean by this. "if it is past zero"? DO you mean the TDC mark passing the pointer?
I did not put my engine together, A reputable shop here in town did it and have not heard any complaints from any customers. Before the engine left the shop I had the guy put it at TDC for me so it would be a little easier on me for the dizzy install. I just think that there is something else wrong other then just a dizzy put in wrong. If i pull the drivers valve cover and rotate the engine until BOTH valves start to close(move downward into the head), then that means I will be on the compression stroke for that cylinderright? Once they stop moving, I should be at TDC on the timing mark on the balancer correct? That is if all is correct right? If so then the dizzy can then be dropped in witht eh rotor tip pointing toward the #1 terminal on the cap. If the rotor isnt in line with the terminal, is it ok to turn the rotor and shaft a little bit until it lines up or will I be messing everything up?

starting from the top of the compression stroke or TDC of the compression stroke no valves are open
then the piston moves down during the power stroke at the bottom of the power stroke the exhuast valve should open up
then the piston moves back up again for the exhuast stroke as the piston reaches TDC of the exhuast stroke the intake valve should open up then the pistons should move back down again

main thing you really need to look for though is is the intake valve opening ( valve spring compression should tell you) when the piston is going up or is it opening when hte piston goes down?

put your motor on TDC ok? just like you did before
how far can you turn the crank till the exhuast valve spring starts to compress? how many rotations of the crank is it?

"I had a budy put his finger on the #1 plug hole and I turned theengine until it started blowing air out. continued to do this until the timing marks started appearing near the pointer."

"I turn the engine until I can feel and hear air pushing out the plug hole. I then check the timing marks on the balancer and they get closer to the timing mark as air pushes out the hole. So that must mean that I am on the compression stroke right?"

wrong. the piston will push air out the plug hole on the exhaust stroke also. you could still be 180 degrees out. the timing mark is at zero at the top of the exhaust stroke too.

I am going to approach this a little different this time. I am going to pul the drivers cover and watch the 2 valve springs on the #1 piston and go from there. Now as I turn the engine by hand(which direction if it matters?) what am I looking for on the valves? I will have a finger on the plug hole waiting for air to push out. what position should those valves be in as I hear this air hissing out the hole so I can drop the dizzy back in.
I have been turning the engine by hand in a CW rotation if it matters to anyone, not sure if there is only 1 way to turn the engine to do this setup. CW if you are looking at the engine from the front the car

so in that order is what I should be looking at to set up TDC then right? watch intake valve move down( spring compresses)then air should start blowing out hole. (I thought both valves must be closed to build compression?)

sorry if I being dumb here but I must be missing something. I need a visual to make this all make sense to me.

im sorry, the intake will be open as the piston goes down on the intake stroke so you'll know that the next stroke as the intake closes will be the compression stroke as the piston comes up.(air pressure builds and blows out the hole) both valves should be closed at this time right up to zero degrees. then install the distributor with th rotor pointing at number one. make a mark or put a piece of tape on some thing on your engine to keep track of where the rotor is pointing then put the cap on. check that the #1 wire on the distributor is lined up with your mark or tape. if everything else is right it should start maybe with a slight advancement of the distributor.

well, found thge problem guys. I sent my MSD dizzy out for a rebuild over the winter and I guess that someone at the shop never pout the roll pin back through the gear on the bottom of the dizzy. I never noticed it when I dopped it in. I cant belive this happened. I only noticed something was wrong when I could turn the rotor on the shaft when the dizzy was seated in the engine. Im not even gona waste my time compalining to MSD. I have been through enought crap with this already this week. I knew that my install steps where right. I thought I was going crazy for a while. At least it was something minor in money terms though.
Thanks for all the advice and tips guys.